Washing compositions and process

ABSTRACT

WATER SOLUBLE SULFITES AND BISULFITES ARE USED TO INCREASE WASHING EFFECTIVENESS OF DETERGENT COMPOSITIONS, ESPECIALLY THOSE CONTAINING BACTERIAL PROTEASE AND/OR BACTERIAL AMYLASE, AND TO GIVE A BUFFERED PH LEVEL, PRACTICULARLY WHERE OTHER COMPONENTS GIVE TOO HIGH A PH WHICH WOULD NORMALLY AFFECT THE STABILITY OF SAID ENZYMES.

b-Z6-73 XR AU 165 EX 3,741,901 Patented June 26, 1973 3,741,901 WASHINGCOMPOSITIONS AND PROCESS Jack Ziffer, Milwaukee, Wis., assignor to PabstBrewing Company, Milwaukee, Wis. No Drawing. Filed Aug. 7, 1970, Ser.No. 62,130 Int. Cl. Clld 3/02 US. Cl. 252--89 9 Claims ABSTRACT OF THEDISCLOSURE Water soluble sulfites and bisulfites are used to increasewashing effectiveness of detergent compositions, especially thosecontaining bacterial protease and/or bacterial amylase, and to give abuffered pH level, particularly where other components give too high apH which would normally affect the stability of said enzymes.

BACKGROUND OF THE INVENTION In recent years the detergent industry hasbeen making strenuous efforts to provide new and improved detergents andespecially detergents having improved washing efficiency. Many articleshave been published on this subject as, for example, The World ofSynthetic Detergents, CW Report, Part One, published in Chemical Weekfor Sept. 20, 1969, pp. 69-74, 78, 80, 89, 91, 93, 94, and 96; The Worldof Synthetic Detergents CW Report, Part Two, Chemical Week for Oct. 29,1969, pp. 80-86, 91, 92, 94, 95, 97, and 98; Detergent IngredientsEffect on Enzymes, published in Soap and Chemical Specialties forSeptember 1969, pages 60, 62, 64, 66, 70, 82, 84, and 90; NTA Gets BigPush in Detergent Powders, published in Chemical and Engineering News,Apr. 6, 1970, pageall; and Nonionics In the 70s, published in Detergentsand Specialties, May 1970, pages 33-36.

It may be noted that the use of enzymes, especially bacterial proteaseand/or bacterial amylase, in washing compositions has increaseddramatically in the last five years, due to the fact that washingefficiency can be increased by the use of such enzymes. Tests forwashing efiiciency have been developed based on the use of an instrumentknown as a Terg-O-Tometer. In general these tests involve washing apretreated swatch of cloth in various types of washing solutions anddetermining the average reflectance (percent white) before and afterwashing. The difference, which is usually referred to as ARd is ameasure of the effectiveness of a given laundry product. The greater theARd, the greater the effectiveness of such product. A laboratory scalemultiple washing machine which simulates the action of the agitator-typehome washer is used for the test. The conditions set forth in thisprocedure for laboratory operations are precise and practical and thereis a high degree of reproducibility of the test data. Two types ofswatches are used which are usually called BMI and CMS. The BMI swatchesare impregnated with blood, milk and India ink and are used where it isdesired to determine the effectiveness of bacterial protease enzymes.The CMS swatches are impregnated with cocoa, milk and starch and areused where it is desired to determine the effectiveness of bacterialamylase enzymes.

Detergents are normally composed of surface active agents and chelatingagents with or without foam boosters, anti-soil redeposition agents,silicates, optical brighteners, borates, enzymes, fillers, organicsolvents, coloring agents and perfume. Sodium tripolyphosphate (hereincalled STP) is the principal chelating agent employed in most presentday detergents but recently phosphates have come under attack because oftheir effect on plant life in streams and ponds and efforts have beenmade to replace at least a part of the phosphates with other substances,for example, trisodium nitrilotriacetatemonohydrate (herein called NTA).This has resulted in compositions that dissolve in water to give ahigher pH. The increased alkalinity tends to destroy the stability ofthe enzymes used in washing compositions and render them less effective.It would therefore be desirable to provide washing compositions and awashing process containing ingredients which make it possible to improvewashing efficiency over a relatively wide alkaline pH, especiallycompositions containing bacterial protease and/or bacterial amylase andto give a buffered pH level, particularly where other components givetoo high a pH which would normally affect the stability of such enzymes.

OBJECTS In view of the foregoing desiderata, one of the objects of thepresent invention is to provide new and improved washing compositionsand a washing process by adding to a detergent composition or to thewash water, especially to detergent compositions or wash waterscontaining bacterial protease and/or bacterial amylase, an ingredientwhich gives a buffered pH level, particularly where other componentsgive too high a pH which would normally affect the stability of suchenzymes, and which when employed in the proper proportions enhances thewashing efficiency.

A more specific object of the invention is to provide new and improvedwashing compositions and a new and improved washing process in whichwater soluble sulfites and bisulfites are employed to increase thewashing effectiveness of detergent compositions, especially thosecontaining bacterial protease and/or bacterial amylase. Other objectswill appear hereinafter.

BRIEF SUMMARY OF THE INVENTION In accordance with the invention watersoluble sulfites and/or bisulfites, preferably sodium sulfite (Na SOsodium bisulfite (NaHSO and/or sodium metabisulfite (Na S O are added todetergent compositions containing surface active agents and chelatingagents with or without other ingredients, or to wash waters containingsuch compositions, in sufficient amount to increase the washingefiiciency and preferably also in amounts sufficient to give a bufferedpH level particularly where other components give too high a pH whichwould normally affect the stability of bacterial protease and/orbacterial amylase enzymes where such enzymes are present in suchcompositions or in wash waters involving the use of such compositions.

The invention particularly contemplates detergent compositions and washwater wherein the pH is around 8 to 12.0 and especially when it iswithin the range of 9.0 to 10.5.

DETAILED DESCRIPTION OF THE INVENTION Most of the detergents todaycontain surfactants, STP and fillers as the principal ingredients. STPis a sequestering agent for calcium and magnesium salts normally foundin hard water. It is a member of the class of materials usually known aschelating agents. NTA is another member of this class of materials whichalso includes the disodium salt of ethylene diamine tetraacetic acid,the tetrasodium salt of ethylenediamine tetraacetic acid, the sodiumsalts of N-(hydroxyethyDethylenediamine tetraacetic acid, and the sodiumsalts of diethylenetriaminepentaacetic acid. Substances such as STP andNTA are sometimes referred to in the art as builders. The surfactantsare sometimes referred to as actives.

Among the surfactants commonly employed are C alkyl benzene sulfonate,and /15 tallow/coconut soap, a C1245 primary alcohol with 9 moles ofethylene oxide, a polyoxypropylene-ethylene oxide condensate with anapproximate molecular weight of 1750 and containing 3 about 80% ethyleneoxide, and a cationic surfactant, dimethyldicocoammonium chloride.

The most commonly used fillter is sodium sulfate. Other fillers aresodium carbonate, sodium sesquicarbonate, sodium bicarbonate and sodiumborate.

Other adjuvants are foam boosters (e.g., lauryl alcohol andcocomonoethanolamide); antisoil redeposition agents (e.g., sodiumcarboxymethyl cellulose); anticorrosion agents (e.g., sodium silicate);optical brighteners; bleaches (e.g., sodium perborate); and enzymes. Thefollowing table, Table I, gives a more specific breakdown of thecomposition of detergents contemplated in the practice of the presentinvention, it being understood that a water soluble sulfite and/orbisulfite is added to such detergents or to wash waters containing themin amounts sufiicient to enhance the washing efficiency. While sodiumsulfite, sodium bisulfite and/or sodium metabisulfite are preferred, thecorresponding water soluble potassium salts can be used but are normallytoo expensive for practical purposes. Other sulfites which are watersoluble and substantially equivalent to sodium sulfite, sodium bisulfiteand/ or sodium bisulfite can also be employed.

The water noluble sulfite, bisulfite and/or metabisulfite preferablyconstitutes 2 to 0.6 part of the detergent. The amount used should besufficient to produce at least 300 parts per million (p.p.m.) of watersoluble sulfite, bisulfite and/or sodium meta-bisulfite in a wash waterand preferably at least 400 p.p.m., calculated as Na SO Usually enhancedeffectiveness is not obtained beyond 1000 p.p.m. and in most cases noimprovement in effectiveness is obtained when the amount is greater than800 p.p.m. It should be noted that sodium meta-bisulfite reacts in equalmolar proportions with water to form 2 moles of sodium bisulfite. Theinvention contemplates the use of mixtures of sodium sulfite and sodiumbisulfite (or sodium metabisulfite) so as to give the wash water abuffered pH usually not exceeding and in most cases not exceeding 9.8.The optimum washing pH range is usually from about 8 to 10. The usualrecommended concentration of detergent in the wash water is 1500 p.p.m.(0.15% weight/volume).

The following table gives compositions in terms of the major componentsof various enzyme based detergent products, some of which are used inthe specific examples hereinafter given. It will be understood thatthese compositions also contain as minor components carboxymethylcellulose, optical brighteners, bleach stabilizers, perfumes, dyes andfree moisture. In the table the quantities are given in parts by weight.

TABLE II B C D 4 The following table illustrates the potency of variouscommercially available enzymes.

It will be understood that the potency of the enzymes can vary ratherwidely. Thus enzymes containing bacterial protease and/or bacterialamylase can be prepared in powdered form having activities within therange of 15,000 to 1,000,000 PV units per gram and 30 to 100,000 DVunits per gram. Normally the enzyme powders contain diluents so that theenzyme activity per gram as added to a detergent base is within therange of 15,000 to 150,000 PV units per gram and 0 to 150,000 DV unitsper gram.

The following table illustrates specific formulations for a high STPdetergent, an NTA-low STP detergent and a low STP detergent using acombination of two of the enzymes given in Table III.

In the table the quantities are given in parts by weight.

TABLE IV I K L STP 70. 00 34. 5o 34. 50 0. 00 24.80 0. 00 0. 1a 0.13 o.13 5. 00 4. 00 4. 00 0. 20 0. 20 o. 20 0. so 0. so 0. so 0. 25 o. 25 0.65 23.92 35.62 60.02

The invention is further illustrated but is not limited by the followingexamples in which the quantities are given by weight unless otherwiseindicated. In these examples washing efficiencies were determined withvarious types of detergents with and without sodium sulfite in variousproportions. BMI or CMS test swatches were used (6" x 3"). Threeswatches were used for each BMI test and five swatches were used foreach CMI test. The washing cycle was 10 minutes at F. The rinse cyclewas 5 minutes at 100 F. and pH values are those of the wash solutions atthe end of the wash cycle. The reflectance was determined with a HunterD25 Color Reflectometer and the ARd readings represent the difference inreflectance before and after each test. The readings were based onaverage readings taken three times on one side and three times on theother side of each swatch. The concentration of detergent in every casewas 0.15% (w./v.) which corresponds to 1500 p.p.m., unless otherwiseindicated. All of the wash tests described in the following exampleswere carried out with city water from Milwaukee, Wis., having a hardnessof p.p.m.

EXAMPLE 1 In this example the detergent used was a commercial detergentbase known as White Magic. The tests were carried out with and without afixed percentage of sodium carbonate and with and without variouspercentages of sodium sulfite. No enzyme was added to the detergent. Thefollowing results were obtained.

Comparing the test results of Example 3 with those of Example 4 it willbe observed that there was an enhanced etficiency when the sodiumsulfite was added where the wash water conatined one gram per liter ofSTP at pHs of 8.6 or 8.7 and also at pHs of 9.5 and 9.6. At a pH of 9.25when a combination of 0.5 g. of STP and 0.5 g. of NTA was used per literof wash water there was no significant improvement with the CMS testcloths but there was a very substantial improvement with the BMI testcloths. Also, there was a significant improvement with both types oftest cloths at higher pH values of 9.7 and 9.8.

EXAMPLE 5 In the following series of sixteen tests, the first four testswere carried out with White Magic detergent base, the next four testswith Punch detergent base, the next four tests with Tide detergent baseand the last four tests with Colgate-Palmolive NTA-low phosphate deter-20 gent base. Enzyme M (Table III) was added in all of these tests.

Percent (w./v.) ingredient in wash BMI test cloth Sodium sulfitedetergent I ARd ARd Sodium carbonate BMI test cloths BMI test clothsPercent (w./v.) ingredient inwash Percent (w./w.) Sodium enzyme added tosulfite detergent None None............-.'.-

It will be noted that an increase in the alkalinity reduced theefiiciency from 24.1 to 23.0 but the addition EXAMPLE 2 The procedurewas the same as in Example 1 except that the detergent base was theNTA-low phosphate detergent base K of Table IV without the enzyme. Thefollowing results were obtained.

Ingredients added per liter of wash solution P t 1 d1 t ercen(glggshngre en Percent (w.lw.) Sodium enzyme added to sulfite detergentaddition of 0.08% sodium sulfite further enhanced the effectiveness ofthe detergent.

of sodium sulfite in the amount of 0.04% more than compensated for thisby raising the efiiciency to 25.6. The

Sodium carbonate None.-.

Sodium carbonate 5.05555 555555555 0 0 0 0 U Q0 0 0 0 0 0 U 0 0 0 ienzymes and STP and NTA with and without the addition of sodiumcarbonate and sodium sulfite. The following results were obtained.

None None.-...........

Here again it will be noted that the loss of efficiency due to increasein alkalinity was more than compensated for by the addition of thesodium sulfite.

EXAMPLE 3 The wash tests were carried out w None-..............

All of the tests show that the washing efliciency decreases at higherpHs with detergents containing enzymes but the addition of sodiumsulfite in quantities of 0.04%

and 0.08% improves the washing efliciency at such pHs.

EXAMPLE 6 CMS test cloths mg. pH ARd Enzyme l mg.

Ingredients added per liter of wash solution Bodium Sodium NTAcarbonsulfite (SJ 8% In this example the washing tests were carried outwith Axion pre-soak base which was added to the wash water in an amountof 0.1% (w./v.). The following results were obtained.

nnmmmmmm 66 5-D aamm w aaa wwwwwwmw Qw3 3 3 3 3 nm3 ARd Madded to Again,it will be seen that the increase in pH reduced the washing efiiciencybut that the addition of sodium sulfite improved the washing efliciencyat the higher pH.

Percent (w./v.) ingredient in wash Sodium carbonate Sodium sulfitedetergent MI test cloths ARd EXAMPLE 7 The series of tests illustratedin this example were carne 785.03%88 880mnm0m .99

(Table III) was added. The results obtained were as follows:

STP (g.)

d out with White Magic detergent base with the addi- 7 tron of variousenzymes. The results were as follows.

Percent (w.Iv.) ingredient in wash Percent BMI test cloths Percent(w.lw.)

(w./w.) enzyme added to enzyme detergent added to Percent (w.lv.) OMSBMI Sodium carbonate Sodium sulfite detagent pH ABd sodium sulfite inEnzyme Enzyme 5 wash M pH Rd pH ARd None 0. M 9.05 37.0 None 0.5 M 9.6534.9 0.25 0.50 9.3 21.3 9.35 29.3 0.04 0.5 M 9. 65 36.9 0.25 0.50 9.322.7 9.35 31.4 0.08 0.5 M 9.6 37.6 0.25 0.50 9.25 24.3 9.35 30.6 None0.5 P 9.1 38.1 0. e5 0. 50 9.3 24.9 9.25 32.7 None 0.5 P 9.1 37.0 0.050.50 9.25 20.4 9.3 34.2 0.04 0.5 P 9.7 38.2 0.65 0,50 9.35 26.1 9.3534.1 0.08 0.5 P 9. 65 38.3 None 0.5 Q 9.1 37.3 None 0.5 Q 9.7 34.5 asits at 1 M R 9, ,7 It will be seen that the addition of 0.04% sodiumsulone 0.5 R 9. 65 36.2 am OJ R 965 37.6 fiiB gave a significantimprovement. 0.08 0.5 R 9.65 38.4

It will be seen that these test results are generally similar to thosedescribed in the previous examples and show that enhanced washingefficiency is obtained by the addition of sodium sulfite, regardless ofthe source of the enzymes.

EXAMPLE 8 This example illustrates the results obtained by combining aparticular type of enzyme with White Magic detergent base with andwithout sodium carbonate and/ or sodium sulfite. The results were asfollows.

Percent In each case the addition of the sodium sulfite at the higher pHgave an enhanced washing efliciency.

EXAMPLE 9 In this series of tests a combination of enzymes was employedwith a Colgate-Palmolive NTA-low phosphate detergent with the additionof various proportions of sodium sulfite. The results obtained were asfollows.

Percent (w.lw.) enzyme Percent (w.lw.) added to detergent CMSrtestcloths sodium sulfite in wash Enzyme M Enzyme 0 pH And BMI test cloths0. 50 None 9. 55 35. 3 0. 50 None 9. 70 35. 2 0. 50 None 9. 70 36. 40.50 None 9. 65 36. 4

EXAMPLE 10 In this series of tests two diflerent enzymes were combinedwith a detergent base containing the ingredients listed for detergentbase L in Table IV excluding the enzymes. The results were as follows.

Percent (w./w.)

Percent (w./v.) ingredient enzyme added in wash to detergent BMI testcloths Sodium Sodium Enzyme Enzyme carbonate M pH A! None 0. 25 0.50 9.15 31. 0 0 None 0. 25 0. 50 9. 55 28. 8 0. 04 0. 25 0. 50 9. 5 31. 1 0.08 0. 25 0. 50 9. 5 31. 0 None 0. 25 0. 50 9. 2 30. 2 None 0. 25 0. 509. 8 27. 3 0. 04 0. 25 0. 50 9. 8 29. 5 0. 08 0. 25 0. 50 9. 75 29. 5 80None 0. 25 0. 50 9. 2 29. 6 None 0. 25 0. 50 10. 05 25. 9 0. 04 0. 25 0.50 10. 05 28. l 0. 08 0.25 0. 50 10.0 27. 6

EXAMPLE 11 In this series of tests a specific enzyme M (Table III) wasadded to an NTA-low phosphate detergent base having a compositioncorresponding to that of detergent K in Table IV, exclusive of theenzymes. The results were as follows.

Percent (w.lw.) Percent (w.lv.) ingredient in wash enzyme BMI test clothM added to Sodium carbonate Sodium sulfite detergent pH ARd N one 0. 59. 1 32. 2 None 0. 5 9. 5 31. 2 0. 04 0. 5 9. 6 32. 6 0. 08 0. 5 9. 533. 0 None 0. 5 9. 1 34. 0 None 0. 5 9. 75 32. 4 0. 04 0. 5 9. 75 33. 10. 08 0. 5 9. 75 33. 4

Again it will be noted that at the higher pH the addition of the sodiumsulfite increased the washing efliciency.

'EXAMPLE 12 In this series of tests the procedure was the same as thatin Example 11 except that a combination of enzymes was employed. Theresults were as follows.

From the foregoing results it is evident that the addition of the sodiumsulfite enhanced the washing efficiency at pHs from 9.5 to 10.05.

Examples 11 and 12 except that CMS cloths were used. The results were asfollows.

Percent (w.w.) enzyme Percent (w./v.) ingredient in wash added todetergent CMS test cloth Sodium Sodium carbonate sulfite Enzyme M EnzymepH ARd None None 0. 25 0. 50 9. 0 28. 1 0.01--." None 0. 25 0. 50 9. 27.2 None 0. 25 0. 50 9. 7 24. 8 None 0. 25 0. 50 9. 95 22. 9 None 0. 25 0.50 9. 0 28.0 None 0. 25 0. 50 9. 4 27. 2 0. 04 0. 25 0. 50 9. 4 28. 5 0.08 0. 25 0. 50 9. 4 28. 8 None 0. 25 0. 50 9. 0 29. 3 None 0. 25 0. 5O9. 7 2d 6 0. 04 0. 25 0. 50 9. 7 29. 4 0. 08 0. 25 0. 50 9. 65 28. 9None 0. 25 0. 50 9. 0 29. 4 None 0. 25 0. 50 10. 0 24. 4 0. 04 0. 25 0.50 10. 0 25. 7 0. 08 0. 25 0. 50 9. 95 26. 0

These results clearly show that the addition of sodium sulfite enhancedthe washing efliciency.

EXAMPLE 14 In this series of tests enzyme M (Table III) was added toWhite Magic detergent base and various proportions of sodium carbonate,sodium sulfite and sodium bisulfite were employed. The results were asfollows.

Percent Percent (w./v.) ingredient in wash (w./w.) enzyme M BMI testcloth Sodium Sodium Sodium added to carbonate sulfite bisulnte detergentpH ARd None None 0. 5 9. 05 38. 2 None None 0. 5 9. 7 36.0 0. 04 None 0.5 9. 8 37. 8 0. 03 0. 01 0. 5 9. 4 37. 3 None None 0. 5 9. 0 38. 1 0.030.01 0. 5 8. 55 40. 7 0.02 0.02 0.5 8. 15 40. 0 0. 01 0. 03 0.5 7. 8 36.2 None None 0. 6 9. 75 37.0 0. 03 0.01 0. 5 9. 4 39. 5 0. 02 0.02 0. 59.05 40. 1 0.01 0. 03 0.5 8. 7 40. 5

These test results show that the combination of sodium sulfite andsodium bisulfite is effective in enhancing washing efiiciency, except inone instance where the pH was 7.8.

EXAMPLE 15 The following tests were carried out with various commercialdeteregnt bases and a pre-soak base without the addition of any enzymeand at pHs from 8.95 to 9.3 with and without the addition of sodiumsulfite. The results were as follows:

Percent Percent so um enzym BMI test cloths Percent (w./v.) sulfite inadded to product in wash wash product pH Rd 0.15 White Magic.. None None9. 1 24. 4 Detergent base..- 0. -.--.do 9.1 26.3

0.16 Punch....-.. None .-.-do 9.0 19.3 Detergent base--- 0.04 do 9. 021. 5

0.1 Axiom None .-.-.do 8.95 17.9 Pre-soak base...-- 0.04 o 8.95 21.0

out enzymes, this loss can be largely compensated for by adding sodiumsulfite or its equivalents. Thus, by using sodium sulfite or itsequivalent it is possible to employ detergents which are more alkaline.This also makes it possible to maintain a desirable washing efiiciencyby replacing at least a portion of the phosphates with other substancessuch as NTA, thereby avoiding the polluting effect of phosphates indisposal waters.

The sodium sulfite and/or sodium bisulfite or their equivalents can beadded to the detergent base or to enzymes which are added to thedetergent base or directly to the wash water. Usually, it is morepractical to make a solid or liquid product in which all of thedetergent ingredients are combined so that the user can add the properproportions to the wash water.

The invention is hereby claimed as follows:

1. In a process of washing textile materials in water, the improvementwhich comprises adding to the wash water a quantity of a substance fromthe group consisting of water soluble sulfites, bisulfites,metabisulfites, and mixtures thereof sufiicient to enhance the washingefficiency of said wash water while maintaining a pH within the range of8 to 12 in said wash water.

2. A process as claimed in claim 1 in which the quantity of saidsubstance is Within the range of 300 to 1000 parts by weight, calculatedas Na sO per million parts by weight of said wash water.

3. A process as claimed in claim 1 in which said substance is sodiumsulfite and the quantity thereof is 400 to 800 parts per million partsof said wash water.

4. A process as claimed in claim 1 in which said wash water has a pHwithin the range of 9.0 to 10.5.

5. A process as claimed in claim 1 in which said wash water comprisessodium tripolyphosphate.

6. A process as claimed in claim 1 in which said wash water comprisestrisodium nitrilotriacetate monohydrate.

7. A process as claimed in claim 1 in which said wash water comprises anenzyme from the group consisting of bacterial protease, bacterialamylase and mixtures thereof.

8. In a process of washing textile materials in water, the improvementwhich comprises adding to the wash water a quantity of a substance fromthe group consisting of sodium sulfite, mixtures of sodium sulfite withsodium bisulfite and mixtures of sodium sulfite with sodiummetabisulfite, said quantity being within the range of 300 parts permillion to 1000 parts per million and being sufiicient to enhance thewashing efficiency of said wash water while maintaining a pH within therange of 8 to 12 in said wash water.

9. A process as claimed in claim 8 in which said wash water contains asubstance from the group consisting of surfactants, chelating agents,sodium sulfate, sodium carbonate, sodium sesquicarbonate, sodiumbicarbonate, so dium borate, borax, sodium carboxy methyl cellulose,sodium silicate, sodium perborate, and enzymes from the group consistingof bacterial protease, bacterial amylase and mixtures thereof.

References Cited UNITED STATES PATENTS 1,452,093 4/ 1923 Pollack 252-2,802,788 8/ 1957 Flaxman 252-105 3,519,570 7/1970 McCarty 252-892,132,579 10/ 1938 Rohm 114 2,958,632 11/1960 Scharz et al. 195-68WILLIAM E. SCHULZ, Primary Examiner US. Cl. X.R.

/5 "i ZsiQ-w 5 22 83 UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent No. 3,741,901 Dated June 26, 973

Inventor(s) Jack Ziffer It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

. "I Column '3, Table I, under "Preferred", opposite "Coloring Agents","0.0-2" should read 0-0.2

Column 5, line 64, "MI" should read BMI line 72, in the table, under"S'IP(g.)", "0.0" should read 1.0

Column 7, line 55, "CMSrtesc" should read CMS test Column 9, line 39,"no.5" should read 40.6

Column 10, line 67, "Scharz" should read Schwarz Signed and sealed this30th day of October 1973.

(SEAL) I Attest:

EDWARD M. FLETCHER,JR. RENE D. TEGTMEYER Attesting Officer ActingCommissioner of Patents

